Highly Enriched Danger

By Alan J. Kuperman and Frank N. Von Hippel

March 21, 2014

NEXT week President Obama will join 57 world leaders in The Hague for the third biannual Nuclear Security Summit. The first two summits played a critical role in phasing out the use of highly enriched uranium as fuel in research reactors to prevent its misuse by states or terrorists to make nuclear weapons.

But the previous conclaves have failed to address the single largest use of such fuel: in nuclear-powered submarines and aircraft carriers. At this summit, world powers must take an important first step toward ending that dangerous and unnecessary practice.

International efforts to end the use of H.E.U. in research reactors began in the 1970s. In its place, engineers developed low-enriched uranium fuels — enriched to less than 20 percent — unsuitable for weapons. These efforts have eliminated half the annual worldwide use of H.E.U. in research reactors, or about 1,700 pounds, enough for 30 nuclear weapons.

But naval reactors use about four times as much H.E.U., over 6,000 pounds per year. The United States is the biggest consumer, using about 4,500 pounds a year, more than the combined total of Russia, Britain and India, the other three navies that use H.E.U. fuel.

Each step of the H.E.U. fuel cycle for naval reactors raises security concerns, from fabrication to shipment to storage before loading into a reactor. Thefts have occurred in both the United States (in the 1960s) and Russia (in the 1990s).

Naval use of H.E.U. also opens the door for other countries to demand the same right. In Iran, the last administration, and more recently 100 members of Parliament, have called for nuclear-powered submarines fueled by H.E.U., which would give it an excuse to produce and possess weapons-usable uranium.

But H.E.U. is not actually necessary for naval reactors. France and China use low-enriched uranium in their nuclear submarines, and Russia has developed an L.E.U. reactor for its next generation of nuclear-powered icebreaker ships.

Congress has tried for 20 years to nudge the Navy into using L.E.U. In 1994, legislators mandated a feasibility study, but the Navy rejected the idea, saying it would increase costs. The Navy’s 1995 report did not, however, consider advanced designs or the security benefits and security cost savings from L.E.U. fuel.

In 2012, the House Armed Services Committee requested an update to the 1995 study. This time the response was more positive, noting the potential to “allow using L.E.U. fuel with less impact on reactor lifetime, size, and ship costs.” Research and development, though, would require up to 15 years and $2 billion.

Still, it would be worth it. If the United States converted to L.E.U., Britain, which depends on America for both its H.E.U. and nuclear submarine technology, would as well. Russia and India could convert to L.E.U. more easily because they use less than fully enriched H.E.U. and, like France, have designed their nuclear submarines to be refueled every 10 years or so. (By contrast, American and British reactor cores are designed to last the lifetime of the vessel.)

By making a decision in principle now, the four countries with H.E.U.-fueled navies could establish an international norm of L.E.U. fuel and pressure new nuclear navies to follow suit.

This also could eliminate a loophole for naval H.E.U. fuel in the proposed Fissile Material Cutoff Treaty, which currently aims to end the production of H.E.U. and plutonium only for weapons.

Upon a phaseout of H.E.U. in both propulsion and research reactors, its production could be banned worldwide for any use, and the United States and Russia could eliminate their huge reserves by diluting them into L.E.U. fuel. The United States alone has 150 tons of weapons-grade uranium set aside for naval fuel — enough for 6,000 nuclear weapons.

It is probably too late to get an agreement on this subject at the coming summit. But President Obama could still announce in The Hague that the United States will start a program to design and test L.E.U. reactors for its next generation of nuclear-propelled naval vessels, and promise to put the issue high on the agenda of the 2016 summit, which will be held in the United States.

Mr. Obama deserves praise for initiating the biannual nuclear summits in 2010. But the process has reached mainly for low-hanging fruit. A more worthy goal would be the worldwide elimination of highly enriched uranium for reactor fuel, which could sharply reduce risks of nuclear proliferation and terrorism.

Alan J. Kuperman is an associate professor at the University of Texas and the editor of “Nuclear Terrorism and Global Security: The Challenge of Phasing out Highly Enriched Uranium.” Frank N. von Hippel is a senior research physicist in the Program on Science and Global Security at Princeton and a co-chairman of the International Panel on Fissile Materials.